When assembling couplings for compressed air or water hoses, it is prior art to use couplings where there is arranged a displaceable locking ring with locking means (e.g. JP-A-09264479), which is adapted for accommodating and fixing a complementary projecting part, so that water, air or another medium may pass through the coupling.
It is a prerequisite that the coupling is designed so that it e.g. is watertight or airtight, entailing that different packings are to be used, and the coupling is to be made in a durable material, which in turn implies that the construction is very complicated and the costs of manufacture are high, which makes this type of coupling unsuited for use in areas where two objects are to be connected/fixed without a medium having to flow between them.
Furthermore, these couplings are to be provided with a closing mechanism so that the medium cannot flow freely from the moment the coupling is disconnected. As the medium is typically under high pressure and/or is flowing with great speed, the connecting and/or releasing is made difficult, as it may be difficult to move the locking ring sufficiently for the locking means to release the projecting part.
The couplings are not known either to be secure against tensile forces, as in their construction no extra safety mechanism is built in which prevents the locking means from disengaging the projecting part.
The couplings are therefore not usable when two apparatuses/units are to be coupled together, and the coupling is subjected to tensile forces.